The removal from air of airborne particles, whether large or microscopic, has been successfully accomplished for many years by prior developed filter systems. At the present time, however, there is a serious need for air handling systems that will permit the safe disposal of hazardous particles, such as viruses, bacteria, and floating particles that are injurious to the human breathing system, general human health and food and food products, which are collected by those prior filter systems.
Some systems for removal from air of airborne particles have utilized a wet process for that removal. An example of a wet collection system is U.S. Pat. No. 4,828,187 which is designed for collection of asbestos. This patent uses a separation chamber into which a nonporous bag is placed for gravity collection of material soaked with water, the vacuum being used to hold the nonporous bag in the separation chamber and not to filter but contain the collected material. Other deficiencies of wet systems are that they are readily plugged by the moist particulate matter and the wet environment presents a particularly advantageous place for growth of collected viruses and bacteria, thus creating a more hazardous condition in the system. The present invention, is directed to a dry process which allows safe disposal of collected hazardous material and eliminates the additional hazards created by the use of a wet collection system.
One situation where there is a special and very acute need for removal of hazardous particles from air is in hospital isolation rooms, areas where hazardous virus or bacteria are handled, environments conducive to the growth of viruses and bacteria and the like. In particular, in hospitals and nursing facilities patients with tuberculosis and other diseases that are communicable through airborne bacteria need to be isolated from other patients, treating personnel and visitors by means of appropriate air filtration systems.